A continuing, widely prevalent problem for the owners and occupants of housing having a basement or other floor at or below grade is presented by the accumulation of water on the floor, leading to damage to furniture and other property and occasionally to structural damage to the building. A similar problem can be presented above grade, particularly in laundry rooms and in other locations in which a plumbing failure may lead to flooding of a floor. Devices for monitoring floor moisture conditions, setting off an audible alarm or visual alarm in the presence of water on the floor, have been proposed. However, such water alarm devices have not been generally accepted for a variety of reasons.
Many of the previously proposed floor water monitoring alarms are unduly complex and expensive for general housing use. Some devices of this nature have been constructed for energization from the electrical power lines in the house, a most undesirable arrangement because power line failures often occur during the kind of storm that is most likely to produce water problems in basements and on floors located at grade.
A particular problem of previously known floor monitoring water alarms is the lack of any convenient means for testing the alarm in the face of impending storm conditions. That is, when a heavy rainstorm is due, the home owner or occupant in a dwelling likely to incur floor water problems needs the reassurance of a convenient and accurate test to determine whether a floor monitoring water alarm is in good operating condition.
Another difficulty associated with previously known floor water alarms is a lack of versatility. The alarm, to be truly effective, should be readily adaptable to simultaneous monitoring of the water level in a sump or a standpipe associated with the floor. By the same token, the sensitivity of the alarm should be established at a level that will not give a false warning under ordinary conditions of dampness in a basement location.